Apparatus and method for evacuating packages

ABSTRACT

A filled flexible receptacle such as a thermoplastic bag containing a food product is evacuated by placing the filled portion of the bag in a first vacuum chamber; extending the neck of the bag into a second and adjacent chamber; evacuating the first chamber thereby causing the bag to balloon outwardly away from the product; and, while the first chamber is being evacuated, evacuating the second chamber and, consequently, evacuating the interior of the ballooned bag; thereafter, when evacuation of the bag is complete, elevating the pressure in the first chamber to collapse the bag firmly around the product and immediately closing the bag thereby making an evacuated package.

United States Patent [191 Burrell 3,832,824 Sept. 3, 1974 APPARATUS ANDMETHOD FOR Primary Examiner-Travis S. McGehee EVACUATING PACKAGESAttorney, Agent, or FirmJohn J. Toney; William D. [75] Inventor: WilliamE. Burrell, Duncan, SC.

[73] Assignee: W. R. Grace & Co., Duncan, SC. [57 ABSTRACT [22] Filed:June 29, 1973 A filled flexible receptacle such as a thermoplastic bagcontaining a food product is evacuated by placing the [2H Appl' 375300filled portion of the bag in a first vacuum chamber; ex-

tending the neck of the bag into a second and adjacent [52] US. Cl.53/22 B, 53/86, 53/112 B chamber; evacuating the first chamber therebycaus- [51] Int. Cl B65b 31/02 ing the bag to balloon outwardly away fromthe prod- [58] Field of Search 53/22 8, 112 B, 79, 86 n n hi the firstchamber is being evacuated, evacuating the second chamber and,consequently, [56] References Cit d evacuating the interior of theballooned bag; thereaf- UNITED STATES PATENTS ter, when evacuation ofthe bag is complete, elevating the pressure in the first chamber tocollapse the bag 3,714,754 2/1973 Holcombe et al 53/112 B X firmlyaround the product and immediately closing the bag thereby making anevacuated package.

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SHEEI HF 4 AAAAAVA A APPARATUS AND METHOD FOR EVACUATING PACKAGES FIELDOF THE INVENTION This invention relates to a method and apparatus forevacuating receptacles, especially impervious, flexible receptacles suchas thermoplastic bags and pouces. The invention has particularapplication in the vacuum packaging of fresh and frozen food productssuch as beef, poultry, ham, cheese, etc.

BACKGROUND OF THE INVENTION A number of methods are available in theprior art for packaging food products such as meat and poultry inflexible containers such as thermoplastic packages and bags. In someprocesses the product is placed in a bag, a vacuumizing nozzle is theninserted into the bag, the mouth of the bag is gathered around thenozzle while the vacuum acting through the nozzle withdraws the air fromthe bag, and after evacuation is completed the bag is either clampedshut with a metal clip or heat welded shut. In this method completeevacuation of the bag is difficult to obtain because the meat product isusually damp and tends to cling to the bag wall so that surface crevicesin the meat will form a pocket with the bag which blocks the passage ofair out of the bag during the vacuumizing process. Accordingly, it isone object of the present invention to provide a method and apparatusfor satisfactorily evacuating bags filled with meat products and thelike.

Rather than insert a nozzle into a filled, impervious pouch or bag,other prior art methods employ a vacuum chamber into which a filled bagis placed in open condition. Subsequent evacuation of the chamber alsoevacuates the bag; and, before the chamber is opened,

the bag is sealed or closed within the chamber. An apparatus forcarrying out such a process is disclosed in U.S. Pat. No. 2,790,284issued on Apr. 30, I957 to P. B. I-Iultkrans. However, the immediatelyforegoing method still does not solve the problem of evacuation of a bagfilled with a crevice containing product such as meat or poultry.Accordingly, it is another object of the present invention to provide amethod and apparatus whereby a package filled with a product which tendsto cling to the package wall may be evacuated and closed within a vacuumchamber.

Another prior art method and apparatus for evacuating a filled bagwithin a vacuum chamber is disclosed in U.S. Pat. No. 3,714,754 issuedon Feb. 6, 1973 to Edward L. Holcombe et al. In the Holcombe et alpatent, the bag loaded with a product is placed in a vacuum chamber andthe neck of the bag is clamped over an extractor which can withdrawvacuum from the bagindependently of the vacuum applied within thechamber. However, this method requires the manual locating of the bagneck around the extractor tube and the manual clamping of the bag neckthereto. Accordingly, it is another object of the present invention toprovide an independent means for evacuating a bag within a vacuumchamber which requires a minimum of manual handling and locating of thebag within the vacuum chamber.

The foregoing and other objects are achieved by the process andapparatus described below.

SUMMARY OF THE INVENTION In one aspect, the present invention is aprocess of evacuating filled receptacles such as thermoplastic bags,pouches, and the like by placing the filled portion of the bag in afirst vacuum chamber, extending the neck of the bag into a second andadjacent vacuum chamber, evacuating the first chamber thereby causingthe bag to balloon outwardly away from the product; and, while saidfirst chamber is being evacuated, evacuating the second chamber and,consequently, evacuating the interior of the ballooned bag; thereafterwhen evacuation of the bag is complete, elevating the pressure in thefirst chamber to collapse the bag firmly around the product andimmediately closing the bag thereby making an evacuated package.

In another aspect, the present invention is a process of evacuating andclosing flexible, impervious receptacles such as pouches, bags, and thelike which have at least one opening and certain at least one product,the process comprising the steps of confining the product containing aportion of the receptacle within a first region, confining a portion ofthe receptacle which contains the opening in a second region so that theinterior of said receptacle is in communication with the second regionthrough said opening of the receptacle, reducing the pressure withinsaid first region and, subsequently, reducing the pressure within saidsecond region so that the interior of the receptacle is evacuated,elevating the pressure in the first region, and, thereafter, closing theopening to make an evacuated package.

In still another aspect, the present invention is an apparatus forevacuating and closing flexible, impervious receptacles such as pouches,bags, and the like which have at least one opening and contain at leastone product and the apparatus comprises a first vacuum chamber with asecond vacuum chamber adjacent to it and an aperture connecting the twochambers for passing the portion of the receptacle containing an openingtherethrough. Means to evacuate the first and second chambers and meansto close the package when its evacuation is completed are included inthe apparatus. Also, the closing means for the apparatus may be either aclip applying device or a heat seal apparatus located within one of thevacuum chambers.

The invention may be better understood by reference to the drawingsdescribed below and the following Description of the PreferredEmbodiment.

DESCRIPTION OF THE DRAWINGS In the drawings which are appended heretoand made a part of this disclosure;

FIG. 1 isa side elevational representation of a preferred apparatusaccording to the present invention in which the vacuum chambers of theapparatus are closed and a chamber wall is removed to show the interiorarrangement;

FIG. 2 is a top plan view of the apparatus shown in FIG. 1 with both ofsaid vacuum chambers open;

FIG. 3 is an isometric representation of a section of the lower portionof both of said vacuum chambers showing a filled package ready to beevacuated;

FIG. 4 is a representation in partial section showing the gathering armsof the preferred closing means of the preferred apparatus;

FIG. 5 shows in partial section a clip being applied to a bag neck whichhas been gathered by the gathering arms shown in FIG. 4;

FIG. 6 shows the clip of FIG. being closed around the gathered bag neckas the clip is forced into the clip anvil;

FIG. 7 is a sectional schematic side representation of the base of thevacuum chambers of the preferred embodiment showing the clip magazineand the clip punch and driving wheel; and,

FIG. 8 is a front elevational representation of the drive and timingwheel shown in FIG. 7.

DEFINITIONS As used herein, the terms listed below will be understood tohave the meaning set forth beside each term:

Receptacle means any container for receiving an article or product to bepackaged in the receptacle and includes bags and pouches.

Bag means a receptacle or container constructed from tubular stock bysealing one end of the tube. A bag may be pleated or gusseted.

Pouch means a receptacle or container constructed from sheet stock. Asingle or multiple sheets may be used; and, commonly a pouch may be madeby folding a single sheet and sealing the free edges of the sheettogether.

Aperture means a hole in a wall that may be of any shape and includesslot, oval, circular, rectangular, and irregular shaped holes. Anaperture may be formed by joining two wall sections that haveindentations in, one or both of the surfaces so joined.

Vacuum means a pressure level lower than atmospheric pressure and may beexpressed in 'lbs./sq.in. or in inches of Hg. A high vacuum means a verylow pressure level.

Heat shrinkable means that the particular material referred to willshrink upon the application of heat.

Heat scalable" means that the particular material referred to can bewelded to itself under the influence of temperature and pressure.

Opening in a receptacle means a passageway from the exterior of thereceptacle to the interior; and, in the tus 1 receives the bag 9 filledwith a product 8 and places the bag on the conveyor 14 and brings theneck of the bag down through the bag neck guide 13 and excase of a bag,the opening can be the bags mouth and the part of the bag containing theopening would -be the bags neck.

PREFERRED EMBODIMENT In FIG. 1, a double chamber vacuumizing apparatus 1is shown in a side elevational representation with the side wall of theapparatus cut away so that the interior arrangement may be clearly seen.Also, reference will be made to FIG. 2 which is a top plan view of theapparatus of FIG. 1 with the hinged cover or head 3 being open. Thecover 3 is hinged to base member 2 which is divided by lower chamberdivider wall 12 which cooperates with the upper divider wall 11 toseparate apparatus 1 into the two chambers or regions 4 and 5. The firstand larger region or chamber 4 is the product chamber in which theportion of a bag or receptacle 9 containing a product 8 is placed onproduct conveyor 14. The receptacle opening or bag neck is extended intothe second and smaller region 5 which serves as the receptacle or bagevacuation chamber. The second chamber 5 is evacuated through vacuumport 7 and the first chamber 4 is evacuated through vacuum port 6.

Looking now at FIG. 3, the extension of the neck of bag 9 from the firstchamber 4 into the second chamber 5 can be more clearly seen. Theoperator of the apparatends the neck of the bag across walls 18a and 18bof the gathering arm track 18, across plunger housing 21, cutter housing22, and the recess 12a in wall 12 so that the opening 9b of the packageis located in the second region or chamber 5 just above the evacuationport 7. The recess 12a in the wall 12 forms the lower half of theaperture in the wall which divides chambers 4 and 5 and this apertureand wall is completed when the cover 3 is rotated into the positionshown in FIG. 1 so that a corresponding recess in wall 11 forms theupper half of the divider wall aperture.

Once the chamber is closed evacuation of chamber 4 begins through vacuumport 6. Any conventional vacuum pump which is well known in the art maybe used and be connected to vacuum port 6 to evacuate chamber 4. Asvacuum is applied the chamber will be evacuated very rapidly, in theorder of 2 to 3 seconds to a low level of pressure or around 27 inchesof Hg. and further reduction in pressure takes a significantly longerperiod of time. The bag neck sufficiently fills the aperture betweenchambers 4 and 5 so that very little air is leaked from the secondregion 5 into the first region 4 during this phase of evacuation. Inthis initial phase, the bag 9 will balloon outwardly as shown by dottedlines 10 because of the difference in pressure between the interior ofthe bag 9 and the chamber 4. This outward expansion of ballooning of thebag also occurs in the bags neck region and the expanded neck furtherseals the aperture between chambers 4 and 5. While the bag is balloonedinto shape 10, evacuation of the second region or chamber 5 is begun.This will usually be of the order of one-half sec. after the beginningof the evacuation of chamber 4. Chiefly because of its smaller size, theevacuation of the second chamber 5 proceeds at a more rapid rate thanthat of first chamber 4 and overtakes the vacuum level in first chamber4 thus causing the ballooned bag 10 to begin to collapse back ontoproduct 8. The second chamber 5 will reach a vacuum level of 28 inchesof Hg. or lower depending on the period of time vacuum is suppliedthrough port 7. As the vacuum level in the second chamber 5 is reducedbelow that in chamber 4 and the bag 9 begins to collapse back upon theproduct 8, atmospheric pressure is restored in chamber 4 by stopping thevacuum pumping action through port 6 and venting the chamber to theatmosphere by valve means which are not shown. This sudden increase inthe pressure differential between the inside and outside of the bag willcause the bag to collapse rather rapidly and suddenly driving out anyremaining air. Immediately as this takes place, the bag is clipped andclosed as will be described more fully hereinafter.

Once the bag is clipped and closed, the excess bag neck material istrimmed off and the head or cover 3 is opened and conveyor 14 will startup and deliver the sealed bag toconveyor 16 while the operator ispreparing to place another filled bag within apparatus 1 to begin theprocess again.

When as described above, the bag balloons outwardly to the shape 10 thebag wall is separated from the product 8 and any crevices or cavities inthe product are exposed to the space which now exists between product 8and the expanded bag wall 10. Thus, when evacuation of the secondchamber 5 begins, a continuous passageway exists whereby a substantialportion of the surface of the product 8 is brought directly under theinfluence of the vacuum being drawn through second chamber 5.

A preferred package or bag closing and sealing means is illustrated inFIGS. 3-7. FIG. 4 is a view in partial section looking along thedirection of lines 4-4 of FIG. 3. This view is from between walls 18aand 18b of the lower gathering arm guide track 18 and between walls 17aand 17b of the upper gathering arm track 17. In FIG. 4 bag neck 9a isshown partially compressed between the bag neck guide 13 and walls 17aand 18a. Gathering arms move inwardly towards each other to furthercompress the bag neck 8 into the shape shown in FIG. 5. As the gatheringarms 25 have moved more closely together to wedge the bag neck 9a into asmaller space, plunger 24 drives clip 37 up around the gathered bagneck9a and forces the clip towards anvil 19. Further motion of theplunger forces the clip into the anvil 19 and bends it into the shapeshown in FIG. 6 securely around the bag neck 19 thereby closing andsealing same. As this is completed cutter arm 26 with serrated cutterblade 27 is driven upwardly to cut off the excess bag material whichextends beyond clip 37. The clip 37 is taken from the group of clips 33contained in clip magazine 32 shown in FIG. 7. The clips 33 are urgedforward in the magazine'32 under the influence of clip spring 34 and aredelivered to plunger 24 immediately below plunger housing 21. Plunger 24is connected to plunger crank arm 29 at pivot 30, and crank arm 29 isdriven by timing wheel 28 to which it is connected by crank pin 35.

Cutter arm 26 is driven upwardly through cutter housing 22 to sever theexcess bag neck material and the drive means for cutter arm 26 is notshown but may be a pneumatically operated cylinder or an electricallydriven solenoid, both of which drive means are well known in the art.

An alternate method and means for closing a package or bag afterevacuation is toremove the bag neck guide 13 shown in FIG. 3 and widenthe aperture opening 12a to correspond to the width of the flattened bagneck. The clip applying means may be eliminated in this alternateclosure means and a sealing bar may be substituted for the blade 27 withthe sealing bar being the same width as the aperture 12a. Bar 27 may beelectrically resistance heated and a pressure backing member may besubstituted for the cutter track 38 as shown in FIG. 6 so that when thearm 26 is driven upwardly after the evacuation of the bag the heated bar27 will contact the flattened bag neck 9a and press same against thepressure backing member 38. The bar would dwell sufficiently long in itsposition of pressing the bag neck against the backing member 38 untilthe bag is sealed to itself. Of course, for this alternate method andmeans to be employed the bag material must be of a type that will weldto itself under the influence of heat and the thermoplastic materialsuch as polyethylene, ethylene vinyl acetate copolymers, saran, and thelike with the appropriate coatings and surface treatments are suitablefor this purpose.

FIG. 8 is a frontal view of the plunger drive wheel 28 which is drivenby pinion 36 which, in turn, is driven by a conventional electricalmotor which is not shown. Crank pin is connected to plunger crank 29 andat the beginning of each cycle crank pin 35 is at bottom dead center ofthe wheel. The time represented by t, is

the time from the beginning of the clips engagement with the anvil tothe end of the engagement as the plunger withdraws. Referring also toFIG. 7, timing cams may be placed on shaft 31 on which wheel 28 ismounted and these cams can be used to control such functions as theventing of the chambers to atmosphere as the clipping and cutting cycleis completed.

Referring now to FIGS. 1-8, a semi-automatic operation of the foregoingdescribed apparatus according to the process of the present inventionwill be described. In the following description valves, cams, a timer,vacuum pump, pressure sensor, etc. are mentioned. None of these areshown in the drawings and each is a conventional item whose use andapplication is familiar to those skilled in the packaging machineryarts. The packaging cycle begins when the operator manually places afilled bag into first chamber 4 and extends the neck into second chamber5. The operator then closes the chambers with cover 3 and the closingactuates a microswitch which starts a timer and opens the valve to port6 so that a vacuum pump can evacuate chamber 4. At a predetermined time,preferably of the order of one-half or five-eighths of a second afterthe evacuation of the first chamber has begun depending on the size ofthe chamber and power of the vacuum pump, the evacuation of the secondchamber is started by the timer opening the valve connecting port 7 withthe vacuum pump. During this time ballooning of the bag 9 to shape 10will have occurred. When the pressure in the first chamber reaches apreset level, preferably about 26 or 27 in. Hg., a pressure sensor .inthe first chamber shuts off the vacuum in the first chamber andsimultaneously sends a signal through a delay timer to the electricdrive motor for pinion 36. At this point, the timing and drive wheel 28is at the position shown in FIG. 8 with the crank pin at bottom deadcenter. The timed signal can be preset for any given duration and ispreferably about 1% seconds which means that wheel 28 will start to makeone complete revolution at the end of that preset period'of time. Timingcams are located on the supporting shaft or axle 31 of wheel 28 and aswheel 28 rotates in a counterclockwise manner (FIG. 8) one of the camswill actuate a valve causing the first chamber to vent to atmosphereprior to reaching time span Venting the first chamber to atmospherecauses the bag 9 to collapse or, rather, be violently pushed against theproduct since the bag interior is at the pressure level of the secondchamber which now will have reached lower than 28 in. Hg. This violentcollapsing of the bag drives out any residual air in. the bagimmediately before the gathering and clipping cycle begins with timespan During 2 the bag neck is gathered and the clipper plunger 24 drivesclip 37 into position around the gathered bag to seal and close same.Following withdrawal of the plunger and'trimming of the bag neck at theend of asecond cam shuts off the vacuum to the second chamber and ventsthat chamber to the atmosphere. The cover 3 may now be raised and whilethe operator is getting another filled bag ready, conveyor 14 moves thecompleted package to exit conveyor 16.

It is to be understood that the present invention is not limited to bagsand pouches but can be applied generally to any receptacle whose wallswill flex outwardly under the influence of a pressure differential andwill conform to a wall aperture. Furthermore, as set forth above, theshape of the wall aperture may be made to conform to the shape of thereceptacle opening and to the closing and sealing method desired.

One particularly desirable package results from the process andapparatus of this invention when a meat or poultry product is enclosedin a heat shrinkable, essentially gas impervious, thermoplastic bag.After the meat product has been sealed in the bag and the resultingpackage conveyed out of the apparatus, the package is passed througheither a hot water bath or through a hot air tunnel to shrink andfurther tighten the bag material around the product. Te tight grip ofthe shrunken material protects 'the product from pinhole leakage becausethe material is so firmly pressed against the product that even when ahole or cut occurs the hole is essentially sealed by the adjacent orexposed portion of the product so that no air can enter the package.

I claim:

1. A process of evacuating and closing flexible, impervious receptaclessuch as pouches, bags and the like which have at least one opening andcontain at least one product comprising the steps of:

a. confining the product containing portion of said receptacle with afirst region;

b. confining a portion of the receptacle which contains said opening ina second region so that the interior of said receptacle is incommunication with said second region through said opening;

c. reducing the pressure within said first region thereby causing atleast a part of said receptacle to move outwardly away from contact withsaid product; and, subsequently,

d. reducing the pressure within said second region and consequentlyevacuating the interior of said receptacle;

e. elevating the pressure in said first region to cause the receptacleto move back into contact with said product; and, thereafter,

f. closing said opening thereby making an evacuated,

sealed, package.

2. The method of claim 1 wherein the reduction in pressure in the secondchamber continues until the pressure in the second region is lower thanthat in the first so that the receptacle has begun to move back againstsaid product before the pressure in the first chamber is elevated.

3. The method of claim 1 wherein said regions are divided by a wallhaving an aperture therein and the portion of the receptacle having saidopening is extended through said aperture.

4. The method of claim 1 wherein said receptacle is a thermoplastic baghaving a neck and a mouth which is the single opening to said bag andincluding the steps of:

i. placing said bags mouth and a portion of said bags neck within saidsecond region while the product containing portion of the bag remains inthe first region; and, after the bag s interior has been evacuated andpressure has been elevated in the first region,

ii. closing said opening by applying a metal clip to the a. providingadjacent first and second vacuum chambers with an aperture connectingsaid chambers;

b. placing the filled portion of the bag in the first vacuum chamber,

c. extending the neck of the bag into the second vacuum chamber, saidbag neck passing through said aperture whereby the mouth of said bag isunrestrained and open within the second chamber;

d. evacuating the first chamber; and, subsequently,

e. evacuating the second chamber thereby evacuating said bag;

f. stopping the evacuation of the first chamber before the evacuation ofthe second is completed; and,

g. closing and sealing said bag.

7. The process of claim 6 including the step of venting said firstchamber to the atmosphere after the evacuation of said chamber hasstopped but before said bag is closed and sealed.

8. An apparatus for evacuating and closing flexible, imperviousreceptacles such as pouches, bags and the like which have at least oneopening and contain at least one product comprising:

a. a first vacuum chamber;

b. a second vacuum chamber adjacent to said first chamber;

c. aperture means connecting said chambers for passing the portion ofsaid package containing an opening therethrough;

d. means to evacuate said first and second chambers independently ofeach other; and,

e. means to close said receptacle when its evacuation is completed.

9. The apparatus of claim 8 wherein said closure means is a metal clipapplying means within said first chamber. 7

10. The apparatus of claim 9 including control means for said evacuationmeans whereby the first chamber will reach maximum evacuation before thesecond chamber. v

11. The apparatus of claim 10 including wherein said closure means is aheat seal means.

12. The apparatus of claim Sincluding means to vent said chambers toatmosphere independent of each other.

13. An apparatus for evacuating receptacles into which a product hasbeen loaded comprising:

a. a first vacuum chamber for receiving the product containing portionof said receptacle;

b. a second vacuum chamber adjacent to said first chamber;

c. a wall separating said chambers, said wall having an aperture thereinthrough which a portion of a receptacle containing an opening may bepassed;

d. means for evacuating and venting the first and second chambersindependently of each other; and,

e. closing and sealing means within said first chamber to close saidreceptacle after evacuation.

14. The apparatus of claim 13 wherein said closing and sealing meansincludes gathering means and clip applying means.

15. The apparatus of claim 13 wherein the means for evacuating andventing the first and second chambers independently of each otherincludes control means whereby said first chamber will reach maximumevacuation before said second chamber.

16. An apparatus for evacuating filled receptacles such as bags,pouches, and the like comprising:

a. a base member divided into first and second chamber bases by a lowerwall, said first chamber base being larger than said second;

b. a cover member hingedly attached to said base member, said covermember being divided by an upper wall into first and second chamberheads;

c. a recess in the upper edge of said bottom wall;

d. a recess in the lower edge of said upper wall, said recesses beingcomplementary whereby when said cover member is rotated to a closedposition first and second vacuum chambers are formed by the mating ofsaid upper and lower walls and an aperture between said chambers isformed by said complementary recesses;

e. a vacuum port in said first chamber;

f. a vacuum port in said second chamber;

g. vacuum pump means in communication with each of said ports;

cle is a thermoplastic bag and said package closure means includes:

1. gathering arms to gather the neck of the bag;

2. clip applying means to apply a clip to said gathered bag neck; and,

3. severing means to cut off excess material extending beyond the bag'sneck.

18. The apparatus of claim 16 wherein said receptacle is a thermoplasticbag and the receptacle closure means is heat seal means.

1. A process of evacuating and closing flexible, impervious receptaclessuch as pouches, bags and the like which have at least one opening andcontain at least one product comprising the steps of: a. confining theproduct containing portion of said receptacle with a first region; b.confining a portion of the receptacle which contains said opening in asecond region so that the interior of said receptacle is incommunication with said second region through said opening; c. reducingthe pressure within said first region thereby causing at least a part ofsaid receptacle to move outwardly away from contact with said product;and, subsequently, d. reducing the pressure within said second regionand consequently evacuating the interior of said receptacle; e.elevating the pressure in said first region to cause the receptacle tomove back into contact with said product; and, thereafter, f. closingsaid opening thereby making an evacuated, sealed, package.
 2. The methodof claim 1 wherein the reduction in pressure in the second chambercontinues until the pressure in the second region is lower than that inthe first so that the receptacle has begun to move back against saidproduct before the pressure in the first chamber is elevated.
 2. clipapplying means to apply a clip to said gathered bag neck; and, 3.severing means to cut off excess material extending beyond the bag''sneck.
 3. The method of claim 1 wherein said regions are divided by awall having an aperture therein and the portion of the receptacle havingsaid opening is extended through said aperture.
 4. The method of claim 1wherein said receptacle is a thermoplastic bag having a neck and a mouthwhich is the single opening to said bag and including the steps of: i.placing said bag''s mouth and a portion of said bag''s neck within saidsecond region while the product containing portion of the bag remains inthe first region; and, after the bag''s interior has been evacuated andpressure has been elevated in the first region, ii. closing said openingby applying a metal clip to the neck of said bag.
 5. The method of claim1 wherein said bag opening is closed by heat sealing the neck wallstogether.
 6. In the process of evacuating filled thermoplastic bags,pouches, and the like, the improvement which comprises: a. providingadjacent first and second vacuum chambers with an aperture connectingsaid chambers; b. placing the filled portion of the bag in the firstvacuum chamber, c. extending the neck of the bag into the second vacuumchamber, said bag neck passing through said aperture whereby the mouthof said bag is unrestrained and open within the second chamber; d.evacuating the first chamber; and, subsequently, e. evacuating thesecond chamber thereby evacuating said bag; f. stopping the evacuationof the first chamber before the evacuation of the second is completed;and, g. closing and sealing said bag.
 7. The process of claim 6including the step of venting said first chamber to the atmosphere afterthe evacuation of said chamber has stopped but before said bag is closedand sealed.
 8. An apparatus for evacuating and closing flexible,impervious receptacles such as pouches, bags and the like which have atleast one opening and contain at least one product comprising: a. afirst vacuum chamber; b. a second vacuum chamber adjacent to said firstchamber; c. aperture means connecting said chambers for passing theportion of said package containing an opening therethrough; d. means toevacuate said first and second chambers independently of each other;and, e. means to close said receptacle when its evacuation is completed.9. The apparatus of claim 8 wherein said closure means is a metal clipapplying means within said first chamber.
 10. The apparatus of claim 9including control means for said evacuation means whereby the firstchamber will reach maximum evacuation before the second chamber.
 11. Theapparatus of claim 10 including wherein said closure means is a heatseal means.
 12. The apparatus of claim 8 including means to vent saidchambers to atmosphere independent of each other.
 13. An apparatus forevacuating receptacles into which a product has been loaded comprising:a. a first vacuum chamber for receiving the product containing portionof said receptacle; b. a second vacuum chamber adjacent to said firstchamber; c. a wall separating said chambers, said wall having anaperture therein through which a portion of a receptacle containing anopening may be passed; d. means for evacuating and venting the first andsecond chambers independently of each other; and, e. closing and sealingmeans within said first chamber to close said receptacle afterevacuation.
 14. The apparatus of claim 13 wherein said closing andsealing means includes gathering means and clip applying means.
 15. Theapparatus of claim 13 wherein the means for evacuating and venting thefirst and second chambers independently of each other includes controlmeans whereby said first chamber will reach maximum evacuation beforesaid second chamber.
 16. An apparatus for evacuating filled receptaclessuch as bags, pouches, and the like comprising: a. a base member dividedinto first and second chamber bases by a lower wall, said first chamberbase being larger than said second; b. a cover member hingedly attachedto said base member, said cover member being divided by an upper wallinto first and second chamber heads; c. a recess in the upper edge ofsaid bottom wall; d. a recess in the lower edge of said upper wall, saidrecesses being complementary whereby when said cover member is rotaTedto a closed position first and second vacuum chambers are formed by themating of said upper and lower walls and an aperture between saidchambers is formed by said complementary recesses; e. a vacuum port insaid first chamber; f. a vacuum port in said second chamber; g. vacuumpump means in communication with each of said ports; h. control meanswhereby one chamber may be evacuated and restored to atmosphericpressure independently of the other; and, i. receptacle closure meanswithin said first chamber to seal said receptacle after evacuation hasbeen completed.
 17. The apparatus of claim 16 wherein said receptacle isa thermoplastic bag and said package closure means includes:
 18. Theapparatus of claim 16 wherein said receptacle is a thermoplastic bag andthe receptacle closure means is heat seal means.